I. Data Set Descriptors A. Title: Steven C. Pennings. 2020. Annual monitoring of mid-marsh grazing scar at eight GCE LTER sampling sites from 2017 - 2025. Georgia Coastal Ecosystems LTER Data Catalog (data set INS-GCEM-2004a; /data/INS-GCEM-2004a) B. Accession Number: INS-GCEM-2004a C. Description 1. Originator(s): Name: Steven C. Pennings Address: Department of Biology and Biochemistry University of Houston Houston, Texas 77204-5513 Country: USA Email: scpennin@central.uh.edu 2. Abstract: Damage by chewing herbivores (grazing scars) was measured at eight sampling sites within the Georgia Coastal Ecosystems (GCE) LTER study area annually in July. Visual surveys were conducted along 8 2m by 10m transects randomly allocated within the mid-marsh zone at each site. Herbivore damage was measured by visually estimating the percent area of leaves missing (grazing scars) to haphazardly chosen leaves along the transect. This survey was conducted as part of the GCE invertebrate monitoring program, and will be performed annually to assess long-term changes in relative species abundances across the GCE study area. In 2024 only 3 sites were sampled due to time and weather constraints. 3. Study Type: Monitoring 4. Study Themes: Terrestrial Insect Ecology, Population Ecology 5. LTER Core Areas: Population Studies 6. Georeferences: none 7. Submission Date: Apr 17, 2020 D. Keywords: abundance, GCE, Georgia, Georgia Coastal Ecosystems, grasshoppers, insects, LTER, marshes, permanent plots, population dynamics, Population Studies, Sapelo Island, species diversity, terrestrial, Terrestrial Insect Monitoring, USA II. Research Origin Descriptors A. Overall Project Description 1. Project Title: Georgia Coastal Ecosystems LTER - V 2. Principal Investigators: Name: Merryl Alber Address: Dept. of Marine Sciences University of Georgia Athens, Georgia 30602-3636 Country: USA Email: malber@uga.edu 3. Funding Period: Jul 01, 2025 to Jun 30, 2031 4. Objectives: The GCE-V project has 5 objectives. Obj. 1 Characterize spatial and temporal patterns in mean and variability of drivers and responses. This will be done by measuring external drivers (e.g., sea level), marsh and estuarine conditions, the wetland biophysical template, and modeling. Obj. 2 Evaluate linkages between external drivers and ecological responses, and determine whether assessing the variability of abiotic drivers improves explanatory power for predicting ecological responses. This will be done by analyzing long-term data and conducting field campaigns in areas with different salinity standard deviations and time-varying inundation, and complementary mechanistic experiments exploring effects of driver variability (e.g., salinity). Obj. 3 Assess disturbances and their effects on patterns of variability in ecological responses. This will be done by tracking response and recovery to natural disturbances in the field and in ongoing experimental manipulations. Obj. 4 Evaluate how ecological properties change across abiotic gradients, and determine whether variability increases near habitat transitions. This will be done using remote sensing, sampling across gradients of salinity and inundation, and establishing new long-term monitoring sites in forested areas to track upland marsh migration. Obj. 5 Determine the mechanisms by which coastal wetlands respond to changing drivers and assess whether variability informs this understanding. This will be done by conducting univariate and multivariate analyses relating key ecosystem variables (e.g., net ecosystem exchange, plant biomass) to drivers (salinity, inundation, temperature), using remote sensing to investigate spatial and temporal patterns in the mean and variability of marsh productivity and their relationship to variability in climate drivers, and synthesizing results to describe net daytime production and above- and below-ground C stocks and how they might change in response to future conditions. 5. Abstract: The Georgia Coastal Ecosystems (GCE) Long Term Ecological Research (LTER) program, which was established in 2000 to understand estuaries (places where salt water from the ocean mixes with fresh water from the land) and their adjacent coastal wetlands (i.e., marshes and tidal forests) and how they respond to long-term change. The GCE LTER researchers evaluate how environmental conditions (e.g., sea level, temperature, storms and hurricanes) and human activities (e.g., land use) affect the properties of estuaries (e.g., salinity, flooding patterns), and how that in turn affects wetlands and their ability to provide food and refuge for fish, shellfish and birds, to protect the shoreline from storms, to help to keep the water clean, and to store carbon, all of which have significant implications for the US economy. Many of the changes that are occurring are affecting not just average conditions, but also their fluctuations and extremes (e.g., variability). For example, not only has the average high tide level increased over the past decade, but the number of extreme flooding events has also increased, both of which have the potential to lead to wetland loss through drowning. During this award, the research team will conduct studies to systematically evaluate 1) whether we can improve our predictions of ecological responses by considering variability in environmental conditions, and 2) the use of variability as an early indicator of underlying environmental stress. The findings from this research will be important for predicting the long-term survival of coastal wetlands in a time of global change. In addition to research, the GCE program works with teachers and students, coastal managers, citizen scientists, and the general public to enhance scientific literacy and improve our understanding of coastal ecosystems. 6. Funding Source: NSF OCE 2425396 B. Sub-project Description 1. Site Description a. Geographic Location: GCE1 -- Eulonia, Georgia, USA GCE2 -- Four Mile Island, Georgia, USA GCE3 -- North Sapelo, Sapelo Island, Georgia, USA GCE4 -- Meridian, Georgia, USA GCE5 -- Folly River, Georgia, USA GCE6 -- Dean Creek, Sapelo Island, Georgia, USA GCE9 -- Rockdedundy Island, Georgia, USA GCE10 -- Hunt Camp, Sapelo Island, Georgia, USA Coordinates: GCE1 -- NW: 081 25 42.53 W, 31 32 48.30 N NE: 081 24 38.64 W, 31 32 48.30 N SE: 081 24 38.64 W, 31 32 02.27 N SW: 081 25 42.53 W, 31 32 02.27 N GCE2 -- NW: 081 19 08.26 W, 31 33 09.19 N NE: 081 17 34.24 W, 31 33 09.19 N SE: 081 17 34.24 W, 31 32 00.97 N SW: 081 19 08.26 W, 31 32 00.97 N GCE3 -- NW: 081 13 59.70 W, 31 32 48.72 N NE: 081 11 44.38 W, 31 32 48.72 N SE: 081 11 44.38 W, 31 30 54.68 N SW: 081 13 59.70 W, 31 30 54.68 N GCE4 -- NW: 081 22 14.71 W, 31 27 48.72 N NE: 081 21 26.12 W, 31 27 48.72 N SE: 081 21 26.12 W, 31 26 54.31 N SW: 081 22 14.71 W, 31 26 54.31 N GCE5 -- NW: 081 21 15.89 W, 31 26 33.14 N NE: 081 19 37.92 W, 31 26 33.14 N SE: 081 19 37.92 W, 31 25 03.50 N SW: 081 21 15.89 W, 31 25 03.50 N GCE6 -- NW: 081 17 58.28 W, 31 23 38.66 N NE: 081 15 51.76 W, 31 23 38.66 N SE: 081 15 51.76 W, 31 22 15.61 N SW: 081 17 58.28 W, 31 22 15.61 N GCE9 -- NW: 081 20 48.23 W, 31 21 29.31 N NE: 081 19 35.38 W, 31 21 29.31 N SE: 081 19 35.38 W, 31 20 21.02 N SW: 081 20 48.23 W, 31 20 21.02 N GCE10 -- NW: 081 17 43.82 W, 31 29 49.29 N NE: 081 15 32.07 W, 31 29 49.29 N SE: 081 15 32.07 W, 31 27 44.35 N SW: 081 17 43.82 W, 31 27 44.35 N b. Physiographic Region: GCE1 -- Lower coastal plain GCE2 -- Barrier island GCE3 -- Barrier island GCE4 -- Lower coastal plain GCE5 -- Barrier island GCE6 -- Barrier island GCE9 -- Barrier island GCE10 -- Barrier island c. Landform Components: GCE1 -- Intertidal salt marsh bordering maritime forest GCE2 -- Intertidal salt marsh GCE3 -- Intertidal salt marsh, mud flat, and maritime forest GCE4 -- Intertidal salt marsh bordering maritime forest GCE5 -- Intertidal salt marsh GCE6 -- Intertidal salt marsh, sand beach, maritime forest GCE9 -- Intertidal salt marsh GCE10 -- Intertidal salt marsh bordering maritime forest d. Hydrographic Characteristics: GCE1 -- Site contains the upper reaches of the Sapelo River, and is subject to 2-3m semi-diurnal tides GCE2 -- Site contains the Sapelo River and associated tidal creeks, and is subject to 2-3m semi-diurnal tides GCE3 -- Site includes Sapelo Sound and portions of Blackbeard Creek, and is subject to 2-3m semi-diurnal tides GCE4 -- Site includes Hudson Creek and is subject to 2-3m semi-diurnal tides GCE5 -- Site contains the Folly River and borders Doboy Sound, and is subject to 2-3m semi-diurnal tides GCE6 -- Site contains Dean Creek and borders Doboy Sound, and is subject to 2-3m semi-diurnal tides GCE9 -- Site contains Crooked Creek and borders the Little Mud River, and is subject to 2-3m semi-diurnal tides GCE10 -- Site borders the Mud River and contains tidal creeks and the upper reach of the Duplin River, and is subject to 2-3m semi-diurnal tides e. Topographic Attributes: GCE1 -- Flat, with elevations ranging from 0-3m above mean low tide GCE2 -- Flat, with elevations ranging from 0-3m above mean low tide GCE3 -- Flat, with elevations ranging from 0-3m above mean low tide GCE4 -- Flat, with elevations ranging from 0-3m above mean low tide GCE5 -- Flat, with elevations ranging from 0-3m above mean low tide GCE6 -- Flat, with elevations ranging from 0-3m above mean low tide GCE9 -- Flat, with elevations ranging from 0-3m above mean low tide GCE10 -- Flat, with elevations ranging from 0-3m above mean low tide f. Geology, Lithology and Soils: GCE1 -- unspecified GCE2 -- unspecified GCE3 -- unspecified GCE4 -- unspecified GCE5 -- unspecified GCE6 -- unspecified GCE9 -- unspecified GCE10 -- unspecified g. Vegetation Communities: GCE1 -- Vegetation is 3/4 Juncus and 1/4 Spartina alterniflora, and upland area is heavily forested. GCE2 -- Spartina alterniflora all tall or medium. GCE3 -- Short and tall Spartina alterniflora, very small amounts of Juncus. GCE4 -- Vegetation is 1/4 Juncus, 3/4 medium and tall Spartina alterniflora. GCE5 -- Dominated by short and medium Spartina alterniflora, with areas of taller S. alterniflora near several small creeks. GCE6 -- Vegetation is mostly short and tall Spartina alterniflora, with small amounts of Juncus and Borrichia. GCE9 -- Low marsh is tall Spartina alterniflora, high marsh has a small amount of medium Spartina alterniflora and lots of Juncus. Some hammocks with upland vegetation. GCE10 -- Vegetation mostly tall and medium Spartina alterniflora, with some Juncus present. Upland heavily forested. h. History of Land Use and Disturbance: GCE1 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No significant disturbance was observed, and no plots were replaced. Oct 16, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C4, C5, C6, C7, C8. The following creekbank plots are on creekbank areas that are collapsing: C5, C6, C8. No disturbance by animal activity was observed and no plots were replaced. Oct 18, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C5, C6, C7 and C8. No disturbance by wrack or wildlife activity was observed, and no plots were replaced. Oct 25, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C7, C8. No disturbance by wrack or wildlife activity was observed, and no plots were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C5, C6. The following plots are on creekbank areas that are collapsing: C18. No disturbance by wrack or wildlife activity was observed, and no plots were replaced. Oct 16, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C2, C16. No disturbance by wrack or wildlife activity was observed, and no plots were replaced. Oct 22, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C3, C15. The following plots were disturbed by wrack or wildlife activity: C17, C18, C25. The following plots are on creekbank areas that are collapsing: C18. No plots were replaced. Oct 27, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C25, C26. The following plots were disturbed by wrack: C17, C18, C36. The following plots were distrurbed by wildlife (some may have no shoots): none. The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 16, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C7. No plots were disturbed or lost, and none were replaced. Oct 19, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C4, C17, C18, C36. The following plots are on creekbank areas that are collapsing: C4, C12, C18, C36. No plots were disturbed by wildlife and none were lost and replaced. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C36 (now C46), C17 (now C27), C18 (now C28). Oct 13, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed due to creekbank: C27, C36. No plots were disturbed by wrack or wildlife activity, and none were replaced. Oct 16, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C27. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C25 (replaced by C35), C26 (replaced by C36). Oct 17, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was noted; however, plots C35, C36 and C28 were renumbered as C45, C46 and C38, but in the same location for unspecified reasons. Oct 20, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C4, C46, C27, C38. The following plots are on creekbank areas that are collapsing (slumping): C4, C45, C27, C38. No plots were disturbed by wildlife. GCE2 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. Plot C6 was disturbed by wrack and Plots C3 and C4 were disturbed by creekbank slumping. Not plots were lost and none were replaced. Oct 18, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C4, C5, C6. The following creekbank plots are on creekbank areas that are collapsing: C2, C6. The following plots were lost due to creekbank erosion or catastrophic wrack disturbance: C1 (replaced with C11). No disturbance by animal activity was observed. Oct 19, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C2. No disturbance by wrack or wildlife activity was observed, and no plots were replaced. Oct 22, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C4, C6, C8. No disturbance by wildlife activity was observed, and no plots were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing: C2, C4. No disturbance by wrack or wildlife activity was observed, no plots were lost due to creekbank erosion, and no plots were replaced. Oct 17, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C12, C4, C6. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C2. The following plots were lost for unknown reasons: C8. No plots were disturbed by wildlife, and no plots were replaced. Oct 23, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C4, C12, C13, C18. The following plots were disturbed by wrack or wildlife activity: C6, C7, C11, C22, C23. The following plots are on creekbank areas that are collapsing: C18. No plots were replaced. Oct 28, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C22, C28. The following plots were disturbed by wrack: none. The following plots were distrurbed by wildlife (some may have no shoots): none. The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 15, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed or lost, and none were replaced. Oct 19, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing: C5, C7, C11, C38. The following plots were lost due to creekbank erosion or catastrophic wrack disturbance: C14, C23 (replaced with C24 and C33, resp.). No plots were disturbed by wrack or wildlife. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C7. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C11 (now C21), C38 (now C48) Oct 13, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by creek bank erosion adjacent to the plot: C17, C24, C42. The following plot was disturbed by wrack: M4. No plots were lost or replaced. Oct 16, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C21 (replaced with C31), C5 (replaced with C15), C17 (replaced with 27). Oct 16, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance or catastrophic wildlife activity: C31, C27 (replaced with C41, C37, resp). Oct 22, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C6. The following plots are on creekbank areas that are collapsing (slumping): C41, C42, C33, C24, C15, C48. No plots were disturbed by wildlife and none were lost and replaced. GCE3 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No significant disturbance was observed, and no plots were replaced. Oct 20, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C4, C5, C6, C7, C8. The following plots were disturbed by wildlife (some have no shoots): M2, M5, M6, M7, M8 (snails). The following creekbank plots are on creekbank areas that are collapsing: C8. No plots were replaced. Oct 19, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C3, C4. The following plots were disturbed by wildlife (some have no shoots): M5, M6. The following creekbank plots are on creekbank areas that are collapsing: C8. The following plots were disturbed by marsh dieback: M7. No plots were lost due to creekbank erosion or catastrophic wrack inundation, and not plots were replaced. Oct 24, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C2, C3, C4, C5, C6, C7. The following plots were disturbed by wildlife (some have no shoots): M5, M7. No plots were lost due to creekbank erosion or catastrophic wrack inundation, and not plots were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance by wrack or wildlife activity was observed, no plots were lost due to creekbank erosion, and no plots were replaced. Oct 15, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C2, C3, C4, C5, C6 (plot C3 has no shoots). The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C6. No plots were disturbed by wildlife, and no plots were replaced. Oct 24, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack or wildlife activity: C1, C2, C3, C4. No plots were lost and none were replaced. Oct 26, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: none. The following plots were disturbed by wrack: C1, C2, C3. The following plots were distrurbed by wildlife (some may have no shoots): M5. The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 17, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed or lost, and none were replaced. Oct 20, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed or lost, and none were replaced. Oct 27, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed and none were replaced. Oct 14, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed and none were replaced, but the following plots were observed to be too far from the creek bank and may be repositioned in the future: C7, C8. A new creek bank tributary is also forming near C5. Oct 18, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C4. The following plots were disturbed by wildlife: M6. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C5 (replaced with C15), C17 (replaced with 27). Oct 18, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C17. Not plots were lost and none were replaced. Oct 25, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C11. The following plots are on creekbank areas that are collapsing (slumping): C11, C12, C14, C28. The following plots were lost due to terminal slumping of the creekbank: C15, C17 (replaced with C25, C27). No plots were disturbed by wildlife and none were lost and replaced. GCE4 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No significant disturbance was observed, and no plots were replaced. Oct 18, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C4. The following plots were disturbed by wildlife (some have no shoots): M6, M8 (snails). No plots were disturbed by creekbank erosion or replaced. Oct 18, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C5, C8. No disturbance by wrack or wildlife activity were observed, and no plots were replaced. Oct 25, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C4. The following creekbank plots are on creekbank areas that are collapsing: C6. No plots were distrurbed by wildlife and no plots were lost or replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing: C6. No disturbance by wrack or wildlife activity was observed, no plots were lost due to creekbank erosion, and no plots were replaced. Oct 16, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C2, C3, C16. No plots were lost or disturbed by wildlife, and none were replaced. Oct 22, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C5, C7, C16. The following plots were disturbed by wrack or wildlife activity: C15, C26, M1, M3. No plots were replaced. Oct 27, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C2. The following plots were disturbed by wrack: none. The following plots were distrurbed by wildlife (some may have no shoots): M3 (no shoots). The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 16, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wildlife: M3 (snails). No plots were disturbed by wrack or were on creekbank areas that are collapsing, and no plots were replaced. Oct 21, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance or catastrophic wildlife activity: C26 (replaced with C36). No plots were disturbed by wrack or wildlife or are on creekbank areas that are collapsing. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C3, C15. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C36 (now C46). Oct 13, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed and none were replaced, but C25 was slightly reposition due to nearby creekbank erosion. Oct 16, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed and none were replaced, but C25 was slightly reposition due to nearby creekbank erosion. Oct 17, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was noted, and not plots were replaced. Oct 20, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing (slumping): C3, C4, C5, C6. The following plots were lost due to terminal slumping of the creekbank: C1 (replaced with C11). No plots were disturbed by wildlife. GCE5 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No significant disturbance was observed, and no plots were replaced. Oct 15, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C6, C7. No disturbance by wrack inundation or animal activity was observed, and no plots were replaced. Oct 18, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C7. No disturbance by wrack or wildlife activity were observed, and no plots were replaced. Oct 23, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C5. No plots were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C7, C8. No plots were distrurbed by wildlife, none were lost due to creekbank erosion, and none were replaced. Oct 17, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C2. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C6. No plots were disturbed by wildlife and none were replaced. Oct 21, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack or wildlife activity: C2, C4, C5, M2. No plots were lost and none were replaced. Oct 28, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: none. The following plots were disturbed by wrack: C3, C5. The following plots were distrurbed by wildlife (some may have no shoots): none. The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 15, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing: C3. No plots were disturbed by wildlife and no plots were lost and replaced. Oct 19, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C5. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C3 (replaced with C13). No plots were disturbed by wrack or wildlife. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C7, C8. The following plots are on sections of creek bank that are collapsing: C5. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C3 (now C13). Oct 13, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plot was disturbed by nearby creekbank erosion: C13. The following plots were disturbed by wrack: C4, C5. Also, two missing markers were replaced at M5. Oct 15, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C13 (replaced with C23). Note that C8 was relabeled as C18 for unspecified reasons. Oct 16, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C5. The following plots were lost due to creekbank slumping: C23 (replaced with C33). Oct 21, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C2, C5. The following plots are on creekbank areas that are collapsing (slumping): C2, C5, C16, C7. No plots were disturbed by wildlife or lost and replaced. GCE6 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to catastrophic disturbance and replaced with new plots as indicated: zone 1, plot 3 (not replaced). Oct 19, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C1. The following plots were disturbed by wildlife (some have no shoots): M6, M7, M8 (snails). The following creekbank plots are on creekbank areas that are collapsing: C4, C5. No plots were replaced. Oct 17, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wildlife (some have no shoots): M8. The following creekbank plots are on creekbank areas that are collapsing: C5. The following plots were lost due to creekbank erosion or catastrophic wrack inundation and were replaced: C2, C4 (replaced with C12, C14). Oct 22, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C12, C23, C5, C6, C8. The following plots were disturbed by wildlife (some have no shoots): M8. No plots were lost due to creekbank erosion, and none were replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C5, C12. The following plots were disturbed by wildlife: M8. No plots were lost due to creekbank erosion, and none were replaced. Oct 15, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C23, C6, C7 (C1, C23 have no plants). The following plots were disturbed by wildlife (some have no shoots): M8. The following creekbank plots are on creekbank areas that are collapsing: C12, C14, C5. No plots were lost and none were replaced. Oct 23, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C5, C14, C22. The following plots were disturbed by wrack or wildlife activity: C15, C16, C23, M8. No plots were replaced. Oct 26, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C24. The following plots were disturbed by wrack: C23. The following plots were distrurbed by wildlife (some may have no shoots): M8 (no shoots). The following plots are on creekbank areas that are collapsing: C22, C23. No plots were replaced. Oct 16, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C22, C23. No other plots were disturbed by wildlife or wrack, and none were replaced. Oct 20, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C6. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C32 (replaced with C42). No plots were disturbed by wildlife or are on creekbank areas that are collapsing. Oct 25, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are located on sections of creek bank that are collapsing: C6, C33. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C15 (now C25). Oct 15, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C6, C8, C33, C34. No plots were disturbed by creekbank erosion or wildlife, but no living plants were observed in C34 and M5 is now in an apparent die-back zone. Oct 16, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C15 (replaced with C25), C16 (replaced with C26), C8 (replaced with 18). Oct 18, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was noted, and no plots were lost; however, plots C33, C34 and C26 were relabeled as C43, C44 and C36, resp. for unspecified reasons. Oct 15, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: M2. The following plots are on creekbank areas that are collapsing (slumping): C42, C36. The following plots were lost due to terminal slumping of the creekbank: C43, C44, C25 (replaced with C53, C54, C35). No plots were disturbed by wildlife. GCE9 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes. Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to catastrophic disturbance and replaced with new plots as indicated: zone 1, plot 4 (added new plot 14). New plots were not in exactly the same locations as lost plots, and so have new numbers. Oct 17, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C5, C6, C8. The following creekbank plots are on creekbank areas that are collapsing: C1, C6. The following plots were lost due to creekbank erosion or catastrophic wrack disturbance: C3 (replaced with C13). No disturbance by wildlife activity was observed. Oct 18, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C1, C2, C6, C13. The following creekbank plots are on creekbank areas that are collapsing: C1, C2, C6. The following plots were lost due to creekbank erosion or catastrophic wrack inundation and were replaced: C5, C7, C8 (replaced with C15, C17, C18). No disturbance by wildlife activity was observed. Oct 23, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C13, C14, C6. No disturbance by wildlife activity was observed, and no plots were lost or replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C2, C18. No plots were distrurbed by wildlife, none were lost due to creekbank erosion, and none were replaced. Oct 14, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C14. No plots were disturbed by wildlife or lost, and none were replaced. Oct 21, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack or wildlife activity: C1, C2, C13. No plots were lost and none were replaced. Oct 25, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: none. The following plots were disturbed by wrack: C2. The following plots were distrurbed by wildlife (some may have no shoots): none. The following plots are on creekbank areas that are collapsing: C1, C13, C16. No plots were replaced. Oct 15, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C1, C13. The following plots were disturbed by wrack: C16. No plots were otherwise disturbed by wildlife or are on creekbank areas that are collapsing and none were replaced. Oct 21, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C16. The following plots are on creekbank areas that are collapsing: C16, C23. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: C2, C11, C14 (replaced with C12, C21 and C24, resp.). No plots were disturbed by wildlife. Oct 24, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C24. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity and were replaced: C16 (now C26), C23 (now C32). Oct 12, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed by creekbank erosion, wrack or wildlife, and none were replaced. Oct 15, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following creekbank plots are on creekbank areas that are collapsing: C18. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife: C21 (replaced with C31), C33 (replaced with C43). Oct 15, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was observed, and no plots were replaced. Oct 21, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No disturbance was observed, and no plots were replaced. GCE10 -- Oct 01, 2000: Permanent plots were established in two nominal marsh zones based on marsh structure -- creek zone and high marsh -- and eight plots were randomly located in each zone and marked with stakes Oct 01, 2001: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No significant disturbance was observed, and no plots were replaced. Oct 20, 2002: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C1, C2, C3, C4, C5, C6, C8. The following plots were disturbed by wildlife (some have no shoots): M5 (snails). No disturbance by creekbank erosion or collapse was observed, and no plots were replaced. Oct 19, 2003: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack (some have no shoots): C3, M1. The following plots were disturbed by wildlife (some have no shoots): M5. The following creekbank plots are on creekbank areas that are collapsing: C2. No plots were replaced. Oct 22, 2004: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C7. No disturbance by wildlife was observed, and no plots were lost or replaced. Oct 21, 2005: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were distrurbed by wildlife, none were lost due to creekbank erosion, and none were replaced. Oct 15, 2006: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. Note that a new zone (zone 3) was added at site GCE10 in 2005. This is a juncus zone in the high marsh. Oct 24, 2007: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack or wildlife activity: C1, C2, C3, C4, C8, M1, M2. The following plots are on creekbank areas that are collapsing: C13. No plots were lost and none were replaced. Oct 26, 2008: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were lost due to creekbank erosion, catastrophic wrack disturbance, or catastrophic wildlife activity: none. The following plots were disturbed by wrack: none. The following plots were distrurbed by wildlife (some may have no shoots): none. The following plots are on creekbank areas that are collapsing: none. No plots were replaced. Oct 17, 2009: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C3. No plots were disturbed by wildlife, and none are on creekbank areas that are collapsing or were replaced. Oct 20, 2010: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed or lost, and none were replaced. Oct 26, 2011: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed and none were replaced. Oct 14, 2012: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C6, C7. The following plots were repositioned due to nearby creekbank erosion: C12, C13. No plots were lost and none were replaced. Oct 13, 2013: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. No plots were disturbed, and none were lost and replaced. Oct 18, 2014: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots were disturbed by wrack: C1, C12, C13, C5. No plots were lost and none were replaced. Oct 24, 2015: Plots were examined for signs of disturbance by wrack inundation, animal activity, and creek bank erosion. The following plots are on creekbank areas that are collapsing (slumping): C1. No plots were disturbed by wrack or wildlife and none were lost and replaced. i. Climate: Climate summary for Sapelo Island, Georgia, based on NWS data from 1980-2010: Daily-aggregated Values: Mean (sample standard deviation) mean air temperature: 20.09°C (7.28°C) minimum air temperature: 15.02°C (7.96°C) maximum air temperature: 24.82°C (6.98°C) total precipitation: 3.26mm (10.3mm) Yearly-aggregated Daily Values: Mean (sample standard deviation) total precipitation (1980-2010): 1124mm (266mm) 2. Experimental or Sampling Design a. Design Characteristics: Grazing scar was determined at eight GCE LTER sampling sites by performing 8 visual transect surveys in the mid-marsh zone at each site. Transects measured 2m x 10m, and were randomly allocated within each site. A leaf was chosen haphazardly along the transect and the percent damage to the leaf was recorded b. Permanent Plots: Permanent plots were established in the marsh areas at each GCE sampling site in October, 2000. Eight plots were placed near drainage creeks (creek zone) and eight were placed in the high marsh (high marsh zone) at each site. c. Data Collection Duration and Frequency: Linear transects were walked by a single observer. Beginning of Observations: Jul 31, 2017 End of Observations: Aug 04, 2025 3. Research Methods a. Field and Laboratory Methods: Grazing scar observation -- A leaf was chosen haphazardly along the transect and the percent damage to the leaf was recorded b. Protocols: none c. Instrumentation: none d. Taxonomy and Systematics: not specified e. Speclies List: f. Permit History: none 4. Project Personnel a. Personnel: Steven C. Pennings b. Affiliations: University of Houston, Houston, Texas III. Data Set Status and Accessibility A. Status 1. Latest Update: 29-Oct-2025 2. Latest Archive Date: 29-Oct-2025 3. Latest Metadata Update: 29-Oct-2025 4. Data Verification Status: Reviewed by IM B. Accessibility 1. Storage Location and Medium: Stored at GCE-LTER Data Management Office Dept. of Marine Sciences Univ. of Georgia Athens, GA 30602-3636 USA on media: electronic data download (WWW) or compact disk 2. Contact Person: Name: Adam Sapp Address: Department of Marine Sciences University of Georgia Athens, Georgia 30602 Country: USA Email: asapp@uga.edu 3. Copyright Restrictions: not copyrighted 4. Restrictions: This information is licensed under a Creative Commons Attribution 4.0 International License (see: https://creativecommons.org/licenses/by/4.0/). The consumer of these data ("Data User" herein) has an ethical obligation to cite it appropriately in any publication that results from its use. The Data User should realize that these data may be actively used by others for ongoing research and that coordination may be necessary to prevent duplicate publication. The Data User is urged to contact the authors of these data if any questions about methodology or results occur. Where appropriate, the Data User is encouraged to consider collaboration or co-authorship with the authors. The Data User should realize that misinterpretation of data may occur if used out of context of the original study. While substantial efforts are made to ensure the accuracy of data and associated documentation, complete accuracy of data sets cannot be guaranteed. All data are made available "as is." The Data User should be aware, however, that data are updated periodically and it is the responsibility of the Data User to check for new versions of the data. The data authors and the repository where these data were obtained shall not be liable for damages resulting from any use or misinterpretation of the data. a. Release Date: Affiliates: Apr 17, 2020, Public: Apr 17, 2020 b. Citation: Data provided by the Georgia Coastal Ecosystems Long Term Ecological Research Project, supported by funds from NSF OCE 2425396 (data set INS-GCEM-2004a) c. Disclaimer: The user assumes all responsibility for errors in judgement based on interpretation of data and analyses presented in this data set. 5. Costs: free electronic data download via WWW, distribution on CD may be subject to nominal processing and handling fee IV. Data Structural Descriptors A. Data Set File 1. File Name: INS-GCEM-2004a_6_0.CSV 2. Size: 576 records 3. File Format: ASCII text (comma-separated value format) 3a. Delimiters: single comma 4. Header Information: 5 lines of ASCII text 5. Alphanumeric Attributes: 6. Quality Control Flag Codes: Q = questionable value, I = invalid value, E = estimated value 7. Authentication Procedures: 8. Calculations: 9. Processing History: Software version: GCE Data Toolbox Version 3.9.10 (23-May-2022) Data structure version: GCE Data Structure 1.1 (29-Mar-2001) Original data file processed: INS-GCEM-2004a.txt (576 records) Data processing history: 29-Oct-2025: new GCE Data Structure 1.1 created ('newstruct') 29-Oct-2025: 576 rows imported from ASCII data file 'INS-GCEM-2004a.txt' ('imp_ascii') 29-Oct-2025: 13 metadata fields in file header parsed ('parse_header') 29-Oct-2025: data structure validated ('gce_valid') 29-Oct-2025: Q/C flagging criteria applied, 'flags' field updated ('dataflag') 29-Oct-2025: automatically assigned study date metadata descriptors based on the range of date values in date/time columns (add_studydates) 29-Oct-2025: updated 1 metadata fields in the Dataset section(s) ('addmeta') 29-Oct-2025: imported Dataset, Project, Site, Study, Status, Supplement metadata descriptors from the GCE Metabase ('imp_gcemetadata') 29-Oct-2025: updated 57 metadata fields in the Dataset, Project, Site, Status, Study, Supplement section(s) ('addmeta') 29-Oct-2025: Q/C Criteria of column Year changed from 'x<2013='Q';x>2023='Q'' to 'x<2013='Q';x>2025='Q' ('ui_editor') 29-Oct-2025: Q/C flagging criteria applied for column(s) Year, 'flags' field updated ('dataflag') 29-Oct-2025: updated 6 metadata fields in the Data section(s) ('addmeta') 29-Oct-2025: updated 15 metadata fields in the Status, Data sections to reflect attribute metadata ('updatecols') 29-Oct-2025: parsed and formatted metadata ('listmeta') B. Variable Information 1. Variable Name: column 1. Year column 2. Month column 3. Day column 4. Site column 5. Transect column 6. Grazing_Scar 2. Variable Definition: column 1. Calendar year of observation column 2. Calendar month of observation column 3. Calendar day of observation column 4. GCE Site column 5. Transect number column 6. Percent damage to leaf 3. Units of Measurement: column 1. YYYY column 2. MM column 3. DD column 4. none column 5. none column 6. percent 4. Data Type a. Storage Type: column 1. integer column 2. integer column 3. integer column 4. integer column 5. integer column 6. floating-point b. Variable Codes: c. Numeric Range: column 1. 2017 to 2025 column 2. 7 to 8 column 3. 1 to 31 column 4. 1 to 10 column 5. 1 to 8 column 6. 0 to 70 d. Missing Value Code: 5. Data Format a. Column Type: column 1. numerical column 2. numerical column 3. numerical column 4. numerical column 5. numerical column 6. numerical b. Number of Columns: 6 c. Decimal Places: column 1. 0 column 2. 0 column 3. 0 column 4. 0 column 5. 0 column 6. 0 6. Logical Variable Type: column 1. datetime (discrete) column 2. datetime (discrete) column 3. datetime (discrete) column 4. nominal (discrete) column 5. nominal (discrete) column 6. data (continuous) 7. Flagging Criteria: column 1. x<2013="Q";x>2025="Q" column 2. x<1="I";x>12="I";x<7="Q";x>8="Q" column 3. x<1="I";x>31="I" column 4. x<1="Q";x>11="Q" column 5. x<1="Q";x>8="Q" column 6. x<0="I";x>100="I" C. Data Anomalies: V. Supplemental Descriptors A. Data Acquisition 1. Data Forms: 2. Form Location: 3. Data Entry Validation: B. Quality Assurance/Quality Control Procedures: C. Supplemental Materials: D. Computer Programs: E. Archival Practices: F. Publications: not specified G. History of Data Set Usage 1. Data Request History: not specified 2. Data Set Update History: Nov 30, 2023: Data from 2023 monitoring added to data set Oct 15, 2024: Data from 2024 monitoring added to data set Oct 29, 2025: Data from 2025 monitoring added to data set 3. Review History: none 4. Questions and Comments from Users: none